Integrations: upstage LLM and Embeddings (#13193)

docs/docs/api_reference/embeddings/upstage.md

docs/docs/api_reference/llms/upstage.md

docs/docs/examples/embeddings/upstage.ipynb

docs/docs/examples/llm/solar.ipynb

docs/docs/examples/llm/upstage.ipynb

...ions/embeddings/llama-index-embeddings-upstage/.gitignore

...egrations/embeddings/llama-index-embeddings-upstage/BUILD

...ations/embeddings/llama-index-embeddings-upstage/Makefile

...tions/embeddings/llama-index-embeddings-upstage/README.md

...x-embeddings-upstage/llama_index/embeddings/upstage/BUILD

...ddings-upstage/llama_index/embeddings/upstage/__init__.py

...embeddings-upstage/llama_index/embeddings/upstage/base.py

...mbeddings-upstage/llama_index/embeddings/upstage/utils.py

.../embeddings/llama-index-embeddings-upstage/pyproject.toml

...beddings/llama-index-embeddings-upstage/tests/__init__.py

...ma-index-embeddings-upstage/tests/integration_tests/BUILD

...ings-upstage/tests/integration_tests/test_integrations.py

...ngs/llama-index-embeddings-upstage/tests/unit_tests/BUILD

...dings-upstage/tests/unit_tests/test_embeddings_upstage.py

...lms/llama-index-llms-solar/llama_index/llms/solar/base.py